NIST Physical Measurement Laboratory Handbook of Basic Atomic Spectroscopic Data

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Atomic Data for Hydrogen (H)

Atomic Number = 1

Atomic Weight = 1.00794

Reference E95

  Isotope   Mass   Abundance   Spin   Mag Moment 


The wavelengths and energy levels given below are for the isotope 1H.

Although the tabulated energy levels comprise values for each level through n = 5, we give (Ritz) wavelengths for resolved fine structures only for the Lyman-alpha, Balmer-alpha, and Balmer-beta lines (1215, 6562, and 4861 Å). As indicated by the energy-level notations in the persistent-lines table, the other wavelengths represent unresolved multiplets. These wavelengths are from the corresponding weighted-average energies.

H I  Ground State 1s 2S1/2
       Ionization energy  109678.7717 cm-1 (13.598433 eV)   Ref. MK00a